Two-dimensional strain echocardiography for detection of cardiotoxicity in breast cancer patients undergoing chemotherapy

Risk Factors for Anthracycline-Induced Cardiotoxicity

Background: Several cardiovascular risk factors have been suggested to be associated with anthracycline-induced cardiotoxicity, but their quantitative effects have not reached a consensus.

Methods: We searched PubMed, EMBASE, and Cochrane Library databases for manuscripts published from inception to February 2021, which reported the results of cardiotoxicity due to anthracycline chemotherapy without trastuzumab. Cardiotoxicity defined by any reduction of left ventricular eject fraction (LVEF) to below 50% or a >10% reduction from baseline was defined as the primary endpoint. Odd ratios (OR) with 95% confidence intervals (CI) were calculated using a random-effects model meta-analysis.

Results: A total of 7,488 patients receiving anthracycline chemotherapy without trastuzumab were included, who had at least one risk factor at baseline. Hypertension (OR: 1.99; 95% CI: 1.43–2.76), diabetes mellitus (OR: 1.74; 95% CI: 1.11–2.74), and obesity (OR: 1.72; 95% CI: 1.13–2.61) were associated with increased risk of cardiotoxicity. In addition, the relative reduction of global longitudinal strain (GLS) from baseline after anthracycline treatment could significantly improve the detection ability of cardiotoxicity (28.5%, 95% CI: 22.1–35.8% vs. 16.4%, 95% CI: 13.4–19.9%) compared with LVEF. The early detection rate of anthracycline-induced cardiotoxicity (3 months after chemotherapy) by GLS was 30.2% (95% CI: 24.9–36.1%), which is similar with the overall result of GLS.

Conclusions: Hypertension, diabetes mellitus, and obesity are associated with increased risk of anthracycline-induced cardiotoxicity, which indicates that corresponding protective strategies should be used during and after anthracycline treatment. The findings of higher detection rate and better early detection ability for cardiotoxicity than LVEF added new proofs for the advantages of GLS in detection of AIC.

Anthracyclines and regional myocardial damage in breast cancer patients. A multicentre study from the Working Group on Drug Cardiotoxicity and Cardioprotection, Italian Society of Cardiology (SIC)

AIMS

In breast cancer (BC) patients treated with anthracyclines-based therapies, we aim at assessing whether adjuvant drugs impact cardiac function differently and whether their cardiotoxicity has a regional pattern.

METHODS AND RESULTS

In a multicentre study, 146 BC patients (56 ± 11 years) were prospectively enrolled and divided into three groups according to the received treatments: AC/EC-Group (doxorubicin or epirubicin + cyclophosphamide), AC/EC/Tax-Group (AC/EC + taxanes), FEC/Tax-Group (fluorouracil + EC + taxanes). Fifty-six patients of the total cohort also received trastuzumab. Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) were calculated before starting chemotherapy (T0), at 3 months (T3), at 6 (T6), and 12 months (T12). A ≥10% drop of EF, while remaining within the normal range, was reached at T6 in 25.3% of patients from the whole cohort with an early decrease only in FEC/Tax-Group (P = 0.04). A ≥15% GLS reduction was observed in many more (61.6%) patients. GLS decreased early both in the whole population (P < 0.001) and in the subgroups. The FEC-Tax Group showed the worst GLS at T6. Trastuzumab further worsened GLS at T12 (P = 0.031). A significant reduction of GLS was observed in all LV segments and was more relevant in the anterior septum and apex.

CONCLUSIONS

The decrease of GLS is more precocious and pronounced in BC patients who received FEC + taxanes. Cardiac function further worsens after 6 months of adjuvant trastuzumab. All LV segments are damaged, with the anterior septum and the apex showing the greatest impairments.

Subtle cardiac dysfunction in lymphoma patients receiving low to moderate dose chemotherapy

Left ventricular (LV) global peak systolic longitudinal strain (GLS) is a sensitive measurement for detecting subtle LV systolic dysfunction and a powerful prognostic predictor. However, the clinical implication of LV GLS in lymphoma patients receiving cancer therapy remains unknown. We prospectively enrolled 74 lymphoma patients (57.9 ± 17.0 years old, 57% male). We performed echocardiographic studies after the 3rd and 6th cycles and 1 year after chemotherapy and a cardiopulmonary exercise test upon completion of 3 cycles of anticancer therapy. Cancer therapy-related cardiac dysfunction (CTRCD) was defined as a ≥ 15% relative reduction in GLS value from baseline. The primary outcome was a composite of all-cause mortality and heart failure events. Thirty-six patients (49%) had CTRCD (LV GLS: baseline vs. after 3rd cycle of therapy: 20.1 ± 2.6 vs. 17.5 ± 2.3%, p < 0.001). CTRCD was detected after the 3rd cycle of anticancer therapy. CTRCD patients had impaired exercise capacity (minute oxygen consumption/kg, CTRCD vs. CTRCD (-): 13.9 ± 3.1 vs. 17.0 ± 3.9 ml/kg/min, p = 0.02). More primary outcome events occurred in the CTRCD group (hazard ratio 3.21; 95% confidence interval 1.04–9.97; p = 0.03). LV GLS could detect subtle but clinically significant cardiac dysfunction in lymphoma patients in the early stage of anticancer therapy. CTRCD may be associated with not only a reduced exercise capacity but also a worse prognosis.

[Clinical Capabilities and Limitations in the Use of Modern Technologies in Echocardiography]

Transthoracic echocardiography is the most frequently used method for detection of impaired contractility of the left ventricle. In most cases, assessment of contractility is carried out visually "by eye", what increases its subjectivity, is operator-dependent in nature and requires a high level of clinical training and experience of the researcher. Currently in the arsenal of a specialist in echocardiography for quantification of left ventricular contractility sometimes is used tissue Doppler echocardiography, however, this method requires special settings of the image (high frame rate, the allocation of zones of interest), depends on the scanning angle and on operator qualification, has high intra - and inter-operator variability, and significantly increases the duration of the study. Therefore, this method has not received wide clinical application. In the 2000s years an innovative technique of speckle tracking emerged, which, unlike tissue Doppler echocardiography is efficient, does not burden a researcher with time costs, has a low intra - and inter- operator variability, does not depend on scan angle. In recent years, this technology is actively implemented in clinical practice for detection of subclinical impairment of the functional state of the myocardium in different diseases and syndromes: arterial hypertension, ischemic heart disease, valvular defects, and congenital heart disease, heart failure, cardiomyopathy of different etiology.

Use of echocardiography to monitor myocardial damage during anthracycline chemotherapy

BACKGROUND

Anthracycline-related cardiotoxicity has a poor prognosis; therefore, early detection of any change in LV function is critical.

OBJECTIVE

The aim of this study was to evaluate the two-dimensional speckle tracking technique for the early detection of cardiac toxicity after low-dose anthracycline chemotherapy in the Chinese population.

METHODS

Forty breast cancer patients were treated by chemotherapy using anthracycline for 4-6 cycles. Patients were examined by echocardiography before chemotherapy (T0) and after the second (T2), fourth (T4), and sixth (T6) cycle. LV ejection fraction (LVEF), LV global longitudinal strain (GLS) and endocardium, mid-myocardium, and epicardium global longitudinal strain (GLS-Endo, GLS-Mid, and GLS-Epi). Additionally, global circumferential strain (GCS), RV global longitudinal strain (RVGLS), and LA global longitudinal strain (LAGLS) were evaluated.

RESULTS

Left ventricular ejection fraction was significantly reduced at T4 (P < 0.05). Compared with T0, GLS, GLS-Endo, GLS-Mid, and GLS-Epi were significantly reduced at T2, T4, and T6 (P < 0.05 for all), the apical septum wall (AS) was also reduced significantly at T2 (P < 0.05), and the apical anterior wall (AA) and the basal anterior wall (BA) longitudinal strains were significantly reduced at T4 (P < 0.05). GCS, RVGLS, and LAGLS were not significantly changed after treatment (P > 0.05).

CONCLUSIONS

LV stratified strains and strain of the segments supplied by the left anterior descending coronary artery are more sensitive to the cardiac toxicity of anthracycline.

Cardioprotective action of the aqueous extract of Terminalia arjuna bark against toxicity induced by doxorubicin

BACKGROUND

The aqueous extract of Terminalia arjuna (TA) bark (TA_AqE) has been shown to have a direct inotropic effect on ventricular myocytes. Active constituents of TA_AqE contain various flavonoids and proanthocyanidins, some of which are known to have antioxidant activities. Whether TA_AqE affords a cardioprotective action against oxidative stress (OS) remains unclear.

PURPOSE

Increased OS is one of the major mechanisms underlying cardiotoxicity induced by doxorubicin (DOX), a commonly-used anticancer agent. The aim of the present study was to investigate potential cardioprotective effect of TA_AqE against DOX-induced OS and cardiac dysfunction.

METHODS

OS and cytotoxicity were induced by 1 µM DOX for 24 h in H9c2 cells, a cardiac tissue-derived cell line, and left ventricular (LV) dysfunction was induced by intrapleural injection of DOX (accumulative 20 mg/kg body weight) to mice. Cellular oxidative levels and morphology were assessed using microscopy and oxidative-sensitive fluorescent dyes with and without co-treatment with TA_AqE. LV function was monitored weekly with echocardiography.

RESULTS

TA_AqE reduced OS and preserved mitochondria and cell growth of H9c2 cells against DOX treatment. TA_AqE (in drinking water) attenuated the decreased LV function and altered myocardial structure caused by DOX treatment.

CONCLUSION

TA_AqE exerts a protective action against cardiotoxicity caused by DOX in part via suppression of OS. Thus, TA_AqE is a promising cardiotonic in adjuvant cancer chemotherapy.